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3 years ago

50 POINTS

Mathematics

1 answer:

lesantik [10]3 years ago

3 0

Answer:

Step-by-step explanation:

Area of sector = ½ r² ∅

1/2 ( 9^2) pi/6

81 x pi/6 x 1/2

81 x (0.52359877559) x 1/2

Area of sector = 21.21

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A bookshelf can hold a maximum of 45 books. Let b represents the number of books to be shelved. Which inequality represents how

leonid [27]

The number of books that can be shelved is 45. So then we know that the amount that need to be shelved <em>can</em> be 45, if the bookshelf had 0 books on it. This means that it can have the equal part of the inequality sign.

However, the amount of book that need to be shelved cannot <em>exceed</em> 45, so b must be less than 45.

Therefore, the answer must be D) b ≤ 45.

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3 years ago

How do you find the length of the curve x=3t−t3x=3t-t^3, y=3t2y=3t^2, where 0≤t≤3√0<=t<=sqrt(3) ?

taurus [48]

It's simple, you just have to do this:

$L=\int\limits_{a}^{b}\sqrt{\left(\frac{dx}{dt}\right)^2+\left(\frac{dy}{dt}\right)^2}~dt$

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$\frac{dx}{dt}=3-3t^2$

$y=3t^2$

$\frac{dy}{dt}=6t$

replacing

$L=\int\limits_{0}^{\sqrt{3}}\sqrt{\left(3-3t^2\right)^2+\left(6t\right)^2}~dt$

$L=\int\limits_{0}^{\sqrt{3}}\sqrt{9-18t^2+9t^4+36t^2}~dt$

$L=\int\limits_{0}^{\sqrt{3}}\sqrt{9+9t^4+18t^2}~dt$

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3 years ago

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Mamont248 [21]

95% confidence interval is given by

x - 2D , and x+ 2D

For 99% confidence interval is

x - 3D , and x + 3D

x = 100000

D = 2000

Then calculate

100000 - 3•2000= 94000

and

100000 + 3•2000= 106000

Now find √D = 44.72

Then interval is

100000 - 44.72 ,. And. 100000 + 44.72

99,956 lower limit and. 100472 upper limit

Then we see that theres only one interval ,

that is between thes 2 limits

ANSWER Is OPTION C) ) ($99.996.46, $100,003.55)

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Daniel [21]

This is the way to solve this

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3 years ago

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4 years ago